Actually I am making a dating site for my client, therefore, I am facing problem to send invite email where our site member can enter the email address of their loved ones and send them to invite email. Please help me out how it’s possible. Your help will be appreciated 
To get started, take a look at the article Corvid Tutorial: Sending an Email on Form Submission .
You can also look at a couple of examples:
Send Email with SendGrid NPM Interface
Send an email using the SendGrid NPM library.
Send Email with SendGrid REST Interface
Send an email using the SendGrid REST API.
Thank you so much Yisrael now it’s working